If you ask 40 neuroscientists the same question you’ll get 40 different answers. In the newly published book Think Tank: Forty Scientists Explore the Biological Roots of Human Experience, Johns Hopkins University neurobiologist David Linden did just that, asking a dream team of leading neuroscientists, “What idea about brain function would you most like to explain to the world?”

Professor of Biological Sciences Alison Barth took Linden’s challenge and contributed a chapter on how our brains change when we use tools. Barth’s research focuses on how the brain changes in response to learning through tactile sensation, the physical way that we interact with the world through touch. In her essay, she explores how our physical perception of self can be rapidly — almost instantly — altered by the things we touch, a form of neural plasticity.

For example, the first time you drove a car, it felt strange and unwieldy — and it was easy to misperceive distances, hit the curb or bump into the parking ticket dispenser. But over time and with practice the car becomes easy and familiar to use, a practical extension of your own body. This mastery is reflected not only in new motor skills, but in a reorganization of somatosensory networks in the brain itself. This plasticity is also apparent when we use other tools — each successive time we use something like a paintbrush or a fork, we extend the edges of our body to include that object. And remarkably, when you step out of the car or put down the fork, your brain immediately reverts to normal, snapping back to its earlier state.

Other chapters in the book are written by experts in behavior, genetics, evolutionary biology and comparative anatomy, and examine a wide variety of topics, including personality, perception, beauty and love.
 

By Jocelyn Duffy | jhduffy@andrew.cmu.edu